Hi Toufiqur,
please find the access information in the hidden content.
I don't think that this is a website specific problem, but the functionality of the helix blog images.
If you delete the images in the copy they are deleted from the server (which I think is a good function).
But because of that they are gone for the original article too.
We migrated this page from Joomla 3 and wanted to get rid of core overrides. In Joomla 3 we had overridden the helix blog options (JS, PHP, etc.) to integrate a second button which unlinked the image from the article without deleting it from the server.
But we do not want to use this overrides anymore because it might cause problems with every update.
If you need any further information, please contact me again.